Luke 3. The Mission of John the Baptist.

3:1 Luke carefully pinpoints the time of John's ministry, again reinforcing his historical perspective. Herod divided Palestine into four districts and gave them to his four sons. A tetrarch is a Roman ruler of a quarter territory, in this case, Judea. One failed so badly that Pontius Pilate was put in his place.

3:2 How did John get started in his work?
"The word of God came to him." He moved when God spoke.

3:4–6 In the language of Isaiah (40:3–5) what was John to do?
"Prepare the way of the Lord."

How was John to do that?
Make straight paths, fill in valleys, bring down mountains. (They had no bulldozers.)
What is a valley? What is a mountain?
A spiritual valley is a refuge, a place one can slide into easily and stay comfortable.
A spiritual mountain is an obstacle difficult to get over.

Let us assume that John went about abolishing the valleys--spiritual refuges and lowering the mountains--eliminating obstacles. How did he do it?

The valley / refuge for Israel was their kinship with Abraham.
"Abraham was represented as sitting at the gate of Gehenna, to deliver any Israelite who otherwise might have been consigned to its terrors. In fact, the ships on the sea were preserved through the merit of Abraham; the rain descended on account of it. For his sake alone had Moses been allowed to ascend into heaven and to receive the Law; for his sake the sin of the golden calf had been forgiven; Daniel had been heard for the sake of Abraham; nay, his merit availed even for the wicked." (Life and Times of Jesus the Messiah. A. Edersheim; Longmans, Green . London,‘96; pg. 271)

3:7 John got rid of this refuge in a forceful way. He called the Jews "a brood of vipers" fleeing the wrath to come. God could make children for Abraham out of stones (?Gentiles). Judgment was prophesied against Israel: "The axe is laid at the root of the trees."

What was the other obstacle, the mountains they faced?
When they asked him what they should do, each group, including tax collectors and soldiers, was told to be generous and fair in money and goods. Materialism was, and is, a hindrance to entering the Kingdom. (3:10–14). Unbelief would be the major issue, especially among the Pharisees and lawyers. Lk.7:24–35
Eventually we will see that even John the Baptist himself would be an obstacle.

What ritual did John require?
3:16. Baptism.
Was baptism a new thing begun by John?
Ritual bathing for purification was part of the Law as found in Lev. 11–15. (~1350BC). Proselytes (Gentile converts) in NT times were to repent, be circumcised and baptized.

Was the baptism of John a new thing? Yes.
Now even native Palestinian Jews were to be baptized, repenting, for the forgiveness of sins. 3:3

Was this different from OT ritual? In OT, circumcision admitted baby males into the covenant relationship. Throughout life, sacrifice and offering renewed the covenant relationship. In John's baptism, adults, presumably male and female, were to repent, and undergo a new crisis experience, a precursor of crisis conversion as we know it.

How did this prepare the way for Christ?
John taught them to deal with sin, repent and make an abrupt change in their attitudes and behavior, as adult Jews.

But John went a step further. When asked whether he was the Christ (3:15), he ducked down and pointed the way to Christ.

Further, God also intervened when Herod put John in prison, removing him from the prospect of forming an ongoing religious movement. It seems harsh, but a false Messiah was a frequent appearance in Israel, and with John's great power and charisma, he would have been unable to stop the movement by himself. "He must increase but I must decrease" (Jn.3:30) was his own confession, but his followers persisted sometime after Pentecost. Acts 10:37; 25:3.

A final step in John's ministry is the baptism of Jesus (3:21). It was like no other baptism before or since. "The Holy Spirit descended upon Him in bodily form as a dove and a voice spoke from Heaven: "Thou art my beloved Son; with Thee I am well pleased." Jesus' deity was publicly demonstrated--and the Trinity was plainly observed. [There is nowhere else in Scripture where the Trinity can be so plainly seen.] The last mountain was flattened and the path to Jesus was straight. It proved to John conclusively that Jesus was the Son of God. Although he had known Jesus before, now he could announce “Behold the Lamb of God who takes away the sin of the world!” Jn.1:29

What valleys do non-Christians today slide into?
Science has disproved God and will solve our problems.
No exclusive religion is permitted. All religions have the same objectives and similar methods.

What mountains must seekers overcome?
•The greatest obstacle is the restraining effect of family and culture.
•The misbehavior of supposedly moral Christians is probably the next greatest obstacle.
•Christians are accused of environmental exploitation and injustice to women and minorities.

How can we make the path straight for our generation? Point people to Jesus. Jesus, not the Church, not the creeds or the manual of membership. Do not excuse moral lapses. Jesus said "And I, if I be lifted up from the earth, will draw all men unto Me. " Jn.12:32 KJV

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PS. Luke's genealogy is believed to be the family of Mary, perhaps starting with her father's name . He traces Jesus through a non-regent son of David, Nathan all the way back to Adam, "the son of God.".
Matthew's genealogy is believed to be the family of Joseph. His genealogy goes from the patriarchs to the kingly line of David and through the exile.

Matthew relates Jesus to Abraham, and emphasizes the important of fulfilled prophecy.
Luke relates Jesus to Adam. Adam and Jesus are compared and contrasted as representatives of the human race in Romans 5 and ICor.15.
We expect Luke throughout his Gospel to point out the universal appeal of Jesus, and his identification with human beings.